1. Field of the Invention
The present invention relates to a method for managing map data for a vehicle, wherein upon display of map data on a display unit by using a navigation system, memory loading for the display of the map data can be quickly performed by reducing the number of access to a physical storage medium with an entire map stored therein.
2. Description of the Related Art
Generally, a navigation system provides functions of calculating a current location of a traveling vehicle using radio signals transmitted by a plurality of satellites belonging to a global positioning system and signals transmitted by sensors of the vehicle, and guiding the vehicle along an optimum path from a starting place to a destination by map-matching the calculated position to map data.
Particularly, in a full navigation system for guiding a vehicle along a path by displaying the path as well as the position of the vehicle, loading of a nationwide map and relevant map data is inevitably required in order to search for a path, guide a travel and visualize a map.
However, due to a large amount of map data and limitations on hardware, it is practically impossible to load such map data on a screen memory. This will be described in detail by way of example with reference to FIG. 1.
FIG. 1 is a view showing a conventional system for managing and displaying map data for a vehicle. As shown in the figure, in the conventional system for managing and displaying map data for a vehicle, when a GPS receiver 100 detects data on the position of the vehicle by receiving GPS data, a control unit 150 retrieves map data related to the position data from a physical storage medium 120 such as a CD-ROM or hard disk. A display driving unit 130 generates a travel guide map for the vehicle using map data retrieved under the control of the control unit 150 in response to input of user command data through a user command input unit 110 so that the map can be displayed on a display unit 140.
However, in such a conventional map data management, map data of a new area should be continuously loaded from a physical storage medium such as a CD-ROM as a vehicle travels. Time required for loading the map data from the physical storage medium causes a considerable delay upon display of a travel guide map for the vehicle.
Therefore, to avoid the time delay of the display, there is a need for improving speed at which the travel guide map is displayed, by minimizing access overhead through reduction in the number of access to the physical storage medium.